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Web-Services Infrastructure for Information Integration in Power Systems Qizhi Chen, Hamada Ghenniwa, and Weiming Shen, Senior Member, IEEE
operations and interoperation among entities require more than just information integration. It requires cooperative interaction and autonomous information sharing. The combination of more dynamic energy markets and the growing importance of E-commerce is driving the greater needs of effective cooperation and information exchange or sharing [1]. Moreover, with the transmission system operating on its security limits, the ability to obtain better-controlled and selfhealing systems with the presence of predictable or Index Terms—Power systems, information integration unpredictable events becomes critical. Many new distributed infrastructure, service-oriented architecture (SOA), Web services, applications have been proposed for the deregulated power information integration, supervisory control and data acquisition grid, needing wide-area or system-based information (SCADA), Intelligent Electrical Devices (IEDs), Web services integration. These applications almost cover all applied areas protocols, IEC61970, IEC61850. of power systems, from operation, control, maintenance, to power market. The information exchange among these I. NOMENCLATURE systems is not longer driven by one-to-one relationship but it should support many-to-many relationship. SOA Service-oriented architecture In fact the information storage of power systems are XML Extensible markup language becoming by nature logically and physically distributed across SOAP Simple object access protocol the entire power grid now. The scattered Intelligent Electrical WSDL Web services description language Devices (IEDs), Substation Automation Systems (SASs), and UDDI Universal description discovery and integration BPEL4WS Business Process Execution Language for Web the smaller dispersed generation units are becoming more important information resources than before. All of them Services include further fine level of useful and detailed information EMS Energy management system related to security analysis, control, maintenance for power ERP Enterprise resource management systems, as well as power market. DMS Distribution Management System All these evolutionary pressures generate new requirements SCADA supervisory control and data acquisition for information integration in a power system. Unfortunately, SAS Substation Automation System the existing solutions for information integration assume IED Intelligent Electrical Devices point-to-point links or gateways for separate special tasks [1]. CIM Common Information Model These solutions only fulfill the short-term information ACS Abstract Communication Services integration needs, and unfortunately, create new information LN Logic Node islands. This paper presents a conceptual framework for a WebII. INTRODUCTION services infrastructure for information integration applied to Deregulation and competitive markets for electricity have changed the organizational structures of the electricity supply power systems and discusses a case study on Web servicesindustry as well as the operation of power systems. Efficient based SCADA (WS-SCADA) in detail. This work aims on building an open, flexible, and scaleable information integration infrastructure with higher cooperation and Q. Chen is with Electrical Engineering School, Southwest Jiaotong integration capability for different users, applications, utilities University, Chengdu, Sichuan, 610031, China. Now she is a visiting professor with Department of Electrical & Computer Engineering,, the University of as well as market participants. It attempts to address Western Ontario, Canada. (e-mail:
[email protected]). integration needs of all system participants and allows them to H. Ghenniwa is with Department of Electrical & Computer Engineering, extend advanced information services to the entire electrical the University of Western Ontario, London, ON, N6G 1H1 Canada (email:
[email protected]). community. This service-oriented infrastructure fulfills the W. Shen is with Integrated Manufacturing Technologies Institute, National long-term information integration needs and facilitates the Research Council Canada, London, ON, N6G 4X8 Canada (e-mail: frequent changes of electrical enterprise applications and
[email protected]). Abstract—This paper identifies new information integration requirements related to operation, marketing, and maintenance of a power system. A Web-services infrastructure for information integration in power systems is proposed. The objective is to develop an open, flexible, and scaleable framework with higher cooperation and integration capability. Some design issues for implementing a Web services-based SCADA (WSSCADA) are addressed as a case study of this novel infrastructure.
1-4244-0493-2/06/$20.00 ©2006 IEEE.
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business challenges. The paper is organized as follows: Section III reviews several related research works on information infrastructures for power system. Section IV briefly introduces the SOA and Web services technology. Section V proposes a Web servicesbased information integration infrastructure for power system. Section VI uses a Web services-based SCADA as a case study of this new infrastructure and some key implementation issues are discusses there. A brief conclusion and future works are addressed in Section VI. III. RELATED WORK There are significant research efforts focused on proposing future information infrastructures for power system. The IT technologies employed by these attempts vary from new communication architecture, Web browser, publish/subscribe middleware to peer-to-peer system. The followings are brief reviews on some related works. After the analysis of the 167 power system disturbances from 1979 to 1995, the work of Xie et al. [2] emphasized on the importance of information systems under the regulated and competitive environment, for which an information architecture for power system was proposed. But the focus was only on constructing the physical communication architecture, without addressing the appropriate information integration and computing paradigms required for the proposed physical information architecture. Qiu et al. [3] discussed the communication issues for the Strategic Power Infrastructure Defense (SPID) system. The work proposed an XML-based Client/Server architecture for information exchange. Despite the utilization of XML, the limitations of C/S architecture, the XML server in this information infrastructure, became the bottleneck for flexible and scaleable information exchange. A new communication architecture called GridStat was proposed in [4]. It is a middleware framework that enables integration through publishing of and subscribing to status information and data that represents dynamic operation. Clearly, the limitation of GridStat is due to its supporting only to control-related applications in the power systems. Astrolabe, a peer-to-peer system, was proposed in [5] for information exchange in power systems. In Astrolabe each node is given a list of peers within the utility Internet and it periodically selects a peer at random time then send an UDPbased gossip message. Astrolabe can be viewed at the message level as a reliable system because where every node is able to track the state of the entire system. This, however, makes it not scalable due to the large amount of information gossips needed for the entire power system, which in turn cause heavy blocking for the communication network. In addition to the communication blocking, the overhead will be encountered by each node in collecting, storing and maintaining some irrelevant and unnecessary information of other nodes. Khatib et al. [6] proposed a new Internet based Power System Information Network Architecture (PSIN) where
information in power systems is posted in WEB pages. Although Web pages really simplified the client applications and standard Internet browser can be used to access the information, this static content-oriented Web pages based architecture did not satisfy the frequent changes of information integration needs. A conceptual overview of a distributed autonomous realtime (DART) system is presented in [7] for the operation of power system. It considered the computing and communications technologies, integrated message/data, and information security as the basic technologies for this largescale autonomous system. It clearly outlined some expecting characteristics of information system in power system for next decade and listed some IT technologies for integrated messaging and data, such as Extensible Markup Language (XML), Web Service Definition Service (WSDL), the Universal Description, Discovery and Integration (UDDI) protocol, etc. But how to construct the integrated information system based on these Web services technologies are not discussed. Although these proposed solutions address some of the challenges for cooperative information integration and exchange in power systems, individually and collectively still have some limitations as discussed above. A more autonomous, yet, cooperative, flexible approaches and technologies are needed in order to construct an interoperable, open, and platform-independent integrated information system for power systems. It is our strong believe that with the development of information technologies, service-oriented computing architecture, Web services, and intelligent agent technology will be the leverage to address all these challenges. IV. SERVICE-ORIENTED ARCHITECTURES AND WEB SERVICES A. Service-Oriented Architecture (SOA) Service-oriented architecture (SOA) is the computing paradigm that utilizes services as fundamental elements for developing applications or systems [8]. Services are autonomy, self-describing, and open components, which support rapid, low-cost composition of distributed applications. Under SOA, no matter a software component or a hardware device can be considered as a service. The service provider encapsulates its service implementations and has the ability to describe service capabilities, interfaces as well as qualities, and to publish these service descriptions to the outside world. Then these services can be discovered, selected, and bound by other distributed applications, which are called service consumers. Basic services, their descriptions, and basic operations, such as publication, discovery, selection, and binding, constitute the SOA foundation. Since services may be offered and communicate over the local network, Intranet, or Internet, SOA provides a distributed computing infrastructure for both intra- and crossenterprise application integration and collaboration [8]. The key characteristics of SOA include [9]: • Autonomy
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• • • •
Interoperability Loose coupling Implementation neutrality Flexible configurability
B. Web Services A Web service is a specific kind of services that is identified by a URI, whose service description and transportation utilize open Internet standards [9]. Laying on the groundwork of service-centric infrastructure and having all SOA’s advantages, Web services-based framework surpasses other service-oriented computing paradigms by their standardization and wide availability. There are three basic components in a Web services-based architecture. They are service provider, service consumer, and service registry. The relationships among them are illustrated in Fig. 1. Web Service Registry Find (UDDI)
Web Service Consumer
SOAP XML
Publish (WSDL)
Web Service Provider
Bind (SOAP) Fig. 1. Web services architecture model
The fundamental technologies of Web services architecture are XML and Simple Object Access Protocol (SOAP). XML is used for standardizing data formats and exchanging data among different platforms. SOAP provides cross-platform inter-application communication support. Web service providers describes their service interfaces using Web Services Definition Language (WSDL) and publish them to the service registry. Server consumers use the Universal Description, Discovery, and Integration (UDDI) APIs to find, locate, and point to a service. Owing to the open standardization of communication protocols, extensible information representation, pervasive Internet technology, and advantages of SOA, Web service provides an appropriate approach for electrical enterprises to build a loosely-coupled, language-neutral, and platformindependent information integration infrastructure to link applications within utilities and across enterprises over the Internet. V. WEB-SERVICES INFRASTRUCTURE FOR INFORMATION INTEGRATION IN POWER SYSTEM A. Web-services Infrastructure for Information Integration In order to implement seamless information integration in a power system, electrical industry makes great efforts to standardize communication protocols and data models. Several standardization efforts of information models
regarding power systems and equipments are published, for example CCAPI and UCA2.0 by EPRI, IEC61970 and IEC61850 by IEC, etc. These standards define the unified common information formats and services interfaces for the interoperation of power production, transmission, distribution, marking, and retailing functions [1]. All these information standards accompanying with prevalent SOA and Web services technology make it possible to build an open, flexible and scaleable infrastructure for information integration. A Web-services infrastructure for information integration in power system is illustrated in Fig. 2. ERP
SCADA
EMS
DMS
Web Service Protocol Stack
SCADA Service UDDI Registry
WSDL
Planning Services UDDI Registry
EMS Services UDDI Registry
IEC61970 XML/CIM
Trading Services UDDI Registry
DMS Services UDDI Registry
IEC61850 LN Class
AM/FM/GIS Services UDDI Registry
ERP Services UDDI Registry
Metadata Repository
Customer Services UDDI Registry
Web Service Protocol Stack Trading
Planning
Customer
AM/FM/GIS
Fig. 2. Web-services infrastructure for information integration in power system
This infrastructure shown in Fig.2 fully utilizes the standard components of Web services, i.e., Web service protocols stack for communication between different systems, WSDL for Web services description, UDDI for services discovery and integration. Metadata repository in Fig. 2 provides all metadata information needed by integrated systems within this infrastructure. It consists of IEC61970 XML/CIM data model [10] for enterprise-level information exchange, IEC61850 Common Logical Node (LN) Classes [11] for station-level information exchange, and WSDL services files for service interface description. Web services protocol stack builds on the top of XML and SOAP standards and a subset of Web services protocols for Security, Messaging, Transactions, and Metadata Exchange should be carefully chosen to satisfy the special information integration requirements for power systems. Each subsystem in this infrastructure is not only the service provider, but may also be the service consumer. Each system describes its own services in WSDL and registers them in the service registry. Services can be inquired by UDDI APIs and
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shared by all other systems in order to satisfy their own interests or business goals. The service UDDI registry for each system can be managed in a centralized way, or distributed over the network as UDDI cloud nodes. In the distributed way, all distributed UDDI registry nodes keep synchronization through UDDI replication API. All services registered in Fig. 2 can be classified into three classes: operation-oriented services, business-oriented services, and maintenance-oriented services. The service classifications and their relationship with different subsystems are illustrated in Fig. 3. SCADA EMS DMS
Operation Services Business
AM/FM/GIS Maintenance Services Services
ERP
Trading Customer
Planning
Fig. 3. Service classifications and relationship with different subsystems
SCADA, EMS and DMS are implemented by operationoriented services, which focus on supplying fast information exchanges and control functions. The publish/subscribe notification mechanism is adopted to automate the data exchange and synchronize the replicated data in various data repositories. Business-oriented services support trading, planning, EPR, and customer systems. The emphasis of these services is on how services are efficiently orchestrated together, how multiple service interactions with different business partners are coordinated to achieve a business goal or add new business values. BPEL4WS (Business Process Execution Language for Web Services) [12] is used here to define the simple interoperable integration model, which facilitates the expansion of automated process integration in both the intraand the business-to-business spaces. Coordination agents can be used for more complicated cooperation among these business-oriented services. Most of maintenance-oriented services request information from this integrated framework. Some of them also publish their information to other systems. Different level of maintenance participants has different information integration needs. For example, a system manager only cares about what kind of a fault is, but a protection engineer wants to know more details about the fault, such as serial event records and fault current curves. In order to satisfy these different information needs of different persons with different roles, WS-Policy [13] is the best choice to define different services characteristics, such as QoS parameters, service granularities, and performance requirements.
B. Key Characteristics This Web-services infrastructure for information integration provides an open, loosely coupled, seamlessly integrated computing paradigm in power system. Its characteristics are highlighted as follows. • Implementation Neutrality: The implementation of each application service and its own complexity are opaque through encapsulation of language or platform differences behind a common interface. Services can be modified without the service’s users being affected. Authorized clients or service consumers can request an information service transparently without knowing what servers, where or how they are attached to the network. • Cooperation Capability: No matter how heterogeneous the hardware or software environments are, the standardized data models, communication protocols, and service interface descriptions easily support the cooperation among different operators, different applications such as process-oriented applications or business-oriented applications, different domains such as intra-enterprise or inter-enterprise, or different power market participants. Depending on agentoriented cooperation and coordination services, the services that are potentially related to a domain or a special process can be automatically located and discovered. • Integration Capability: Based on common ontology, information services can be easily integrated with other services either statically or dynamically. Lower-level services can be composed into higher-level services, and legacy applications can be easily encapsulated or wrapped into a new environment. • Scalability: Based on the same services repository, systems or applications with different sizes can be easily implemented by composing different number or types of services. Except that, this infrastructure provides the flexibility to facilitate frequent changes of enterprise application. When new business challenges arise, new applications for them can be implemented by recomposing existing services, or by adding new business services into the system. When a new service is added, it publishes its service description to the UDDI registry, then any other systems can know its existence, then request and employ them. • Flexibility: Services in this infrastructure can be easily reconfigured or replaced. Service deployment can be conducted incrementally and scaling can take place over time. • Security: Security is an important issue for power systems. Firewalls are needed in this integrated infrastructure in order to isolate or minimize the possibility that unauthorized users access, modify or destroy any critical information. WS-Security service [14] (WSS) provides a
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framework within which authentication and authorization take place, so it should be applied in this Web services-based architecture. Web Services Security offers a trusted means for applying security to Web services by providing the necessary technical foundation for higher-level services. WSS builds upon existing security technologies such as XML Digital Signature, XML Encryption and X.509 Certificates to deliver an industry standard way of securing Web services message exchanges. VI. CASE STUDY: IMPLEMENTATION ISSUES OF A WEB SERVICES-BASED SCADA Supervisory Control and data acquisition (SCADA) system plays a very important role in a power system. It supports control of remote equipments, gathers data from substations and generation stations, and shares all the gathered information with other systems, such as EMS, Trading, Planning, and EPR systems. SCADA is the most important information resource for power system operation, maintenance as well as marketing. This section takes a Web services-based SCADA (WS-SCADA) system as a case study for the proposed infrastructure for information integration in power system, and discusses some.implementation issues of this WSSCADA system. A. Distribution of UDDI Registry The typical hierarchical structure of a SCADA system is illustrates in Fig. 4.
broker. The service brokers in control center or in substations separately maintain their own services registries and cooperatively respond the intra- or inter-system services requests. The architecture of service broker in this hybrid mode is illustrated in Fig. 5. Control Center Service Broker
Substation1 Service Broker
Substation1 Service Broker
Substation1 Service Broker
Fig. 5. Architecture of service broker in hybrid registry
Centralized registry makes the control center as the system bottleneck. In the meantime, the control center has a risk of overload. Peer-to-peer registry floods the communication network with information related with services publishing or inquiry. Hybrid mode makes a balance between centralization and peer-to-peer methods, so it is the best choice to manage the Web service UDDI registry. Fig. 6 shows this hybrid service registry structure in WS-SCADA. Customer
Planning
EMS/DMS
EPR
Trading
AM/FM/GIS
IEC61970 CIM/XML Metadata/ Web Services Protocols Stacks UDDI Registry Broker
Control Center
Control Center Control Center Services Substation1
Substation2
Substation1 Services
Substation n Services
Substationn Web Services Protocols Stacks
IED1
IEDn
IED1
IEDn
IED1
IEDn
Fig. 4. Hierarchical structure of SCADA
The most important design issue for a Web services-based SCADA system is to manage its UDDI registries [15]. Under the hierarchical structure shown in Fig. 4, there exist three totally different methods for Web services registry management. • Centralized registry: All Web services are centralized registered in the control center and managed by one service broker. • Peer-to-peer registry: UDDI registries are totally distributed in every level of a SCADA system. Control center, substations, and IEDs separately maintain their own services registry and publish them to the entire SCADA system. There does not exist any service broker in this situation. • Hybrid registry: Unlike the approach used in the peer-topeer mode, IEDs here do not publish their services directly to the entire SCADA system. Instead IEDs register their services in the substation registry managed by substation service
UDDI Registry Broker Substation Services
UDDI Registry Broker Substation Services
IED1 ACSs
IED1 ACSs
IEDn ACSs
IEDn ACSs
Substation1
Substation n
Fig. 6. Hybrid registry structure in WS-SCADA
In Fig. 6, the services supplied by the control center are coincident with API interfaces defined in IEC61970 standard [10], which include GDA (General Data Access) service, HSDA (High Speed Data Access) service, GES (General Eventing & Subscribing) service and TSDA (Time Serial Data Access) service. The substation services registered in the control center are same as those registered in substations. These two registry
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copies are for backup purposes and cooperate with each other to accomplish distributed computation. The services supplied by substations mainly include control services, alarm services, data acquisition services, fault analysis services, and data validation & synchronization services, etc. The services registered by IEDs in a substation UDDI registry are coincident with IEC61850 standard [11], and can be derived from their ACS (Abstract Communication Services) definitions. B. Protocols Stack for a Web services-based Control Center Web service specifications documented in [16] provides a variety of interoperable protocols for Security, Reliable Messaging, and Transactions in the loosely coupled Web service-based SCADA system. Considering the special security and real-time requirements of a SCADA system, the configuration of protocol stack for a control center in a WSSCADA is shown in Fig. 7. Application protocols UDDI WSDL WS-Policy WS-MetadataExchange XML IEC61970 CIM/XML
WS-Security WS-Addressing WS-Enumeration WS-Eventing SOAP SOAP-over-UDP HTTP
UDP
TCP Ipv4/Ipv6
Ethernet or SDH/ATM/MPLS Fig. 7. Protocol stack for a Web services-based control center
The lower layers in this protocol stack are same as the legacy system. Ethernet in data-link layer is used for the connection between SCADA and EMS or other systems in the same control center. SDH/ATM/MPLS provides a wide area network to connect the control center with substations, other control centers, and other systems. All other protocols in addition to the application protocols in this stack are related to Web services specifications. They can be classified into three types: metadata-, messaging-, and security-related protocols. 1) Metadata-related protocols WS-Policy [13] is used to express the capabilities, requirements, and general characteristics of services as policy assertions. In a WS-SCADA system, priority policy, communication QoS characteristics, transport protocol selection, and information granularity etc., will be the candidates of the policy assertions. Because requirements for services properties may vary to different applications, WSPolicy provides a mechanism to negotiate how to use a service in a particular application context. WS-MetadataExchange [17] allows service consumers to retrieve metadata associated with a requested Web service,
such as service descriptions, policies, or XML schema. This provides a cooperation mechanism between the service consumers and the service providers. 2) Messaging-related protocol SOAP [18] is one of the basic protocols in the Web services specifications. It is used for transporting servicerelated messages formatted in accordance with the corresponding WSDL definitions. Because of its extensibility feature, many other Web services protocols are constructed upon it. In order to minimize the network connection overload or support application protocols using UDP or multicast transmission, SOAP-over-UDP [19] may be employed in these situations. WS-Addressing [20] provides transport-neutral mechanisms to address Web services information and messages. It concentrates all messages addressing information into the header of the SOAP message envelope, thereby allowing that the message content can be carried over any transport protocols, or through networks that include processing nodes such as firewalls, and gateways. WS-Enumeration [21] supplies a streaming information transferring mechanism to those applications for which a simple single-request/single-reply metaphor is insufficient for transferring large data sets over SOAP. In WS-SCADA WSEnumeration is used for database query, event records retrieving etc. WS-Eventing [22] protocol describes how a subscriber (event sink) to register event messages interest (subscription) with another Web service (event source) to get event message (notification), and defines a simple, asynchronous, publishsubscribe event delivery mechanism-Push Mode. Control center in a WS-SCADA system uses notification to push control messages to substation, and uses WS-Eventing protocol to state its information subscription request from substation. The information includes status information and real–time operation data, such as voltage, current, breaker status, and phasor measurement data. In order to avoid unnecessary notification from substation, filter may be defined in the control center’s subscription statement. 3) Security-related protocol WS-Security [14] includes a broad set of specifications for ensuring end-to-end information security. Considering the high security requirements and the balance between security and real-time response requirement, the security mechanism of a WS-SCADA may be implemented by employing WSSecurity: SOAP Message Security (providing quality of protection through message integrity, message confidentiality, and single message authentication), WS-Trust (managing security tokens and trust relationships), and WSSecurityPolicy (indicating the policy assertions for using WSSecurity and WS-Trust). C. Protocols Stack for a Web services-based Substation The configuration of protocol stack for a substation in a
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WS-SCADA is shown in Fig. 8. The protocol configuration in Fig. 8 is almost the same as the control center’s shown in Fig. 7, besides adding WSDiscovery and IEC61850 ACS. But the use of WS-Eventing protocol is a little bit different from the one in control center. Application protocols IEC61850 ACS UDDI WSDL WS-Policy WS-Discovery XML IEC61850 LN Classes
WS-Security WS-Addressing WS-Enumeration WS-Eventing SOAP SOAP-over-UDP HTTP
UDP
TCP Ipv4/Ipv6
Ethernet or SDH/ATM/MPLS Fig. 8. Protocol stack for a Web services-based substation
WS-Discovery [23] is a discovery protocol to be used in substation to locate services provided by IEDs. It is built upon SOAP-over-UDP in order to minimize the network traffic overload. According to IEC61850, each IED corresponds to a physical device that may house one or more logical nodes. A logical node (LN) has a standardized function and data model. Each LN can be considered as a service and discovered by a multicast probe. When an IED join the LAN in a substation, it announces its LN services by sending a multicast Hello message. When leaving the LAN, it announces this through a Bye message. Thus the Plug-and-Play for IEDs in a WSSCADA substation is easily achieved by this multicast discovery protocol. IEC61850 ACS [11] is defined as a set of generic abstract services which cover all the data transfers required within a substation. Given a practical application protocol, ACS and LN data can be mapped into the real protocol. Through this abstract communication services definition, when application protocol changes, the only thing needed to do is to map these abstract services into the new protocol. WS-Eventing [22] plays two roles in a substation. On the one hand, it is used by Substation Automation System (SAS) to push notifications to the SCADA control center or other systems, and to subscribe notifications from different IEDs. On the other hand, WS-Eventing is used by IEDs to push notifications to SAS. Since several measurements taken by different IEDs may be related to the same signal, there is some redundant information among different IEDs. Some coordination mechanisms should be adopted to avoid these redundancies, no matter before IEDs sending the notifications or after SAS receiving this information. Agent technology may be an appropriate choice to implement these coordination mechanisms.
VII. CONCLUSION The proposed Web-services infrastructure for information integration in power systems overcomes the shortcomings caused by traditional point-to-point or gateway solutions to the information integration problems. It can accommodate information needs of all system participants and adapt to dynamic changes of electrical enterprise applications as well as business challenges. Owing to the standardized data model and communication protocols, extensible information representation, pervasive Internet technology, and advantages of SOA, this Web services-based information integration infrastructure is an open, flexible, scaleable framework with higher cooperation and integration capability to link applications within utilities and across enterprises over the Internet. After the analysis of the implementation issues for a Web services-based SACADA system, it shows that a hybrid UDDI registry combining with centralization and peer-to-peer characteristics is the best choice to manage services registering information under this infrastructure. By choosing proper standard protocols configuration, the secure, real-time, and standard-based communication mechanisms can be achieved among different subsystems. In our future research, we will try to combine this Web services-based infrastructure with agent technology in order to enhance its intelligence and robustness. The research emphasis will be on knowledge-based Web services orchestration engine, agent-based coordination mechanism among service brokers, and agent-based proactive process for real-time information to reduce information redundancy in substations. VIII. REFERENCES [1]
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IX. BIOGRAPHIES
Qizhi Chen received her B.Sc. degree and M.S. degree in electrical engineering in 1991 and 1994 from Southwest Jiaotong University (SJU), Chengdu P.R. China. She is an Associated Professor in SJU,
majoring in SCADA, power system automation, network communication, and advanced IT technologies used in power system. Now she is a Visiting Professor with Department of Electrical & Computer Engineering, the University of Western Ontario, ON, Canada.
Hamada Ghenniwa is the Director of Software Engineering, at the Department of Electrical and Computer Engineering, University of Western Ontario. He is also the Co-Director of Cooperative Distributed Systems Engineering group at the University of Western Ontario. His main research expertise includes computational intelligence with a specific focus on intelligent agent technology, coordination theory, as well as its application to cooperative distributed systems. Application areas include enterprise integration, electronic business, manufacturing, intelligent mobile robotics, collaborative engineering, pervasive and grid computing. Dr Ghenniwa is currently leading several research and industrial projects concerned with integration in distributed information systems, e-Business and multi-agent systems for manufacturing and mobile robotics. He has authored and co-authored more than 80 papers in world-class journals and conference proceedings as well as several technical and industrial project reports
Weiming Shen (Senior Member, IEEE) is a Senior Research Officer at National Research Council Canada’s Integrated Manufacturing Technologies Institute and an Adjunct Professor at the University of Western Ontario. He is also the Co-Director of Cooperative Distributed Systems Engineering group at the University of Western Ontario. He has been working on intelligent agents and their applications to engineering design, intelligent manufacturing and virtual enterprises for more than 13 years. He has published one book and about 200 papers in scientific journals and international conferences/workshops, and co-edited 12 conference/workshop proceedings in the related areas. He is a Senior Member of IEEE, a member of ASME, ACM and AAAI. He is a registered Professional Engineer in Ontario.
